Add ACS branch limit and implement printKill

Implements Environment::printKill, so that errors that interrupt ACS scripts (branch limit, unknown opcode or function, OOB branch) are shown in the console.

Also, sets the environment's branch limit, to prevent runaway scripts from freezing the game.

Please provide more detailed descriptions the intended change; not all maintainers have context into the ACS VM library and so won't fully understand what is being changed.

approved this merge request

merged

mentioned in commit f25367b9

For future MRs: these two changes are distinct and should be added as separate commits to assist in bisection.

changed the description